1. Field of the Invention
The invention relates to a common rail injector for injecting fuel in a common rail injection system of an internal combustion engine, having an injector housing, which communicates with a central high-pressure reservoir and in which a nozzle needle is axially displaceable in order to adjust the injection as a function of the pressure in a control chamber, and having a sealing element, which is disposed in an annular chamber that is provided between a valve element and the injector housing.
2. Description of the Prior Art
In common rail injection systems, a high-pressure pump pumps the fuel into the central high-pressure reservoir, which is known as a common rail. From the high-pressure reservoir, high-pressure lines lead to the individual injectors, which are assigned to the engine cylinders. The injectors are triggered individually, each via a respective control valve, by the engine electronics. When the control valve opens, fuel subjected to high pressure moves past the nozzle needle, which is raised counter to the prestressing force of a closing spring, into the combustion chamber.
In conventional injectors, of the kind described for instance in European Patent Disclosure EP 0 604 915 B1, a soft sealing ring is used as the sealing element.
The object of the invention is to lengthen the service life of the known injectors by simple means. Nevertheless, despite a longer service life, the injector of the invention should be capable of being produced economically.
In a common rail injector for injecting fuel in a common rail injection system of an internal combustion engine, having an injector housing, which communicates with a central high-pressure reservoir and in which a nozzle needle is axially displaceable in order to adjust the injection as a function of the pressure in a control chamber, and having a sealing element, which is disposed in an annular chamber that is provided between a valve element and the injector housing, this object is attained in that in addition to the sealing element, a support device is disposed in the annular chamber between the valve element and the injector housing.